(1) Field of the Invention
The invention relates to a mobile power plant with the features of the preamble of claim 1, the application of such a mobile power plant with the features of the preamble of claim 9 and a method of operating the mobile power plant with the features of the preamble of claim 12. The invention lies in the technical field of mobile power plants of helicopters.
(2) Description of Related Art
A helicopter is conventionally provided with a rotary wing for providing it with lift and propulsion and with an anti-torque tail rotor for countering the torque exerted by the rotary wing on the fuselage of the helicopter. Furthermore, a helicopter features energy supply systems, e.g., electric, hydraulic, compressors for air-con systems, driven by a drive system of the helicopter. Some of said energy supply systems, e.g., hydraulics, are required to be driven by a rotor drive system to keep them operational also in case of loss of all engines/autorotation, see FAR and CS 27/29.691 and 695. At least bigger helicopters are required by FAR and CS 29,671c to have means to check full availability of the flight controls in their entire range prior to take-off. The transfer of the mechanical rotational power from the engine to the drive system e.g., a main gear box (MGB)—is done via a free wheel mechanism. This allows free rotation of the drive system and rotor, e.g., for autorotation, should the engine fail, see FAR and CS 27/29.691 and 695.
In order to drive the rotary wing, and where appropriate the anti-torque rotor, the helicopter has a power plant.
The power plant implements one or more engines. It should be understood that throughout this specification, the term “engine” applies equally well to turbine engines or to piston engines. The term “engine” is to be contrasted with the term “electric motor”, where the term “electric motor” designates a motor driven by electricity, preferably a so-called “brushless” motor for example.
The document US 2011/121127 A1 discloses a power plant having a single engine together with both a main gear box (MGB) suitable for driving the rotary wing of a helicopter and a tail gear box (TGB) suitable for driving an anti-torque rotor of a helicopter. The power plant also includes a first electric motor mechanically connected to said MGB in order to be capable of driving said MGB, and a second electric motor mechanically connected to said TGB in order to be capable of driving said tail gear box.
An object of the present invention is to propose a mobile power plant for the demand for further electrical/hydraulical energy—at least for specific elements/parts. It is a further object of the present invention to propose an application of said mobile power plant for the demand for further electrical energy during the production life of helicopters at least for specific elements/parts of a flight mission. It is a still further object of the present invention to propose a method of operating the mobile power plant with or without engine.
A solution is provided with a mobile power plant with the features of claim 1 of the invention. A further solution for an application of said mobile power plant is provided with the features of claim 9 of the invention. A still further solution for a method of operating said mobile power plant is provided with the features of claim 12 of the invention.